Electrodeposition and extraction of zinc.



UNITED .s'rAS PA URLYN CLIFTON TAInTon, or 'Lonnon, AND Jenn NORMANrams,

' ENGLAND.

ame

. I ELECTBODEPOSITION' AND EXTRACIZtON orzmo.

No Drawing.

To all whom. it may concern:

Re i known that we, URLYN Gmr'rox TAINTON, a Subject of the King ofEngland, residing at 1 London Wall Buildings, London. England, and JOHNNORMAN Pnmc, D. Sc, a subject of the King of England, residing at LindenBank, Sandbach, Chester, England, have invented certain new and usefulImprovements in the Electrodeposition and Extraction of Zinc, of whichthe following is a specification.

This invention is for improvementsin orv relating to theelectro-deposition and ex-' traction of zinc, and it is a modificationof the invention described in the prior United States Patent No.1059233.

In the said patent specification a process for the electrolyticdeposition of metallic zinc from its: salts is described which consistsin adding to a solution of the salt a prior 'Patent No. 1059233mentioned above canbe secured by the process as described in suchspecification without the presence of any colloid. Zinc can be sodeposited economically, although the deposits are deficient insmoothness and devoid of luster, matters which for many purposes are oflittle, if any consequence.

Accordlngto the present invention, therefore, the process for theelectrolytic deposition of metallic zinc from its salts, the a subjectof the said United States Patent No.

1059233, is carried out without the presence of any colloid. The processis applicable to the production of deposits of zinc where smoothness andluster are of little or no importance. 4

The solution employed 'is preferably ,a

60 saturated solution of zinc sulfate and the acid is preferablysulfuric acid.

One example of a method of carrying the .present invention into effectWlll now be described. A solution for depositin zinc con- 66 sisting ofa saturated solution 0 zinc sul- 'amperes per square foot. 'rent densitythe deposits obtained were specification of Letters Patcnt. PatentedNov. 20, 191 '7. Application filed November 7, 1916. Serial No. 130,101.

fate in water to which is added 16% of 5111- furic acid, and containingno colloid agent- 18 employed. If it is required to deposit the zinc ona metal article, the article is placed in the solution and connected tothe electrical supply as the cathode, the anode being formed of eitherzinc or any substance which does not go into solution, as for ex--ample, lead, lead p'eroxid, or manganese diemployed'in the electrolyticdeposition of zinc. For example, the density may be 600 firm, and thecurrent efficiency was 94.6%.

The'process may conveniently be used for extracting zinc from its ores,in which case the zinc is dissolved with an acid to form a solution of asalt of zinc, as for example With this curzinc sulfate, which is thenelectrolyzed' as described above, or the cyclic process described in theco-pending application Serial No. 14837 is' employed, in whichthe-solution is regenerated by dividing it into two portions, treatingfresh ore with one portion" thereof to dissolve zinc and neutralize itsacid content, and thereafter mixing the neutral solution with theremaining portion for further treatment by electrolysis with a currentof high density, (for example 50 to 1000 amperes per square foot), thepropor-.

tion employed for treating the fresh ore preferably being such that onneutralizing the acid content with fresh ore and mixing the resultingneutral solution with'the remaining solution, the-mixture contains from5 to 30% of free acid. 1

What'we claim as our invention and desire to secure by Letters Patent isi I 1. A process for the extraction of metallic zinc from azinc-containing material which consists in forming a solution of thezinc free from any 'collold agent and con taining a large percentage ofacid, and electrolyzing 1t with a current of high density.

2. A process for the extraction of metal-' lic zinc from its salts whichconsists in adding to a solution of the salt free from any colloid agenta large percentage of acid and electrolyz'ing it with a current of highdensity,

3. A process for the extraction of metallic zinc from zinc sulfate whichconsists in the extraction of zinc from a zinc-bearing same as that ofthe original solution, and

salt free from adding to a solution of the sulany colloid agent a largeproportion of furic acld and electrolyzing: the solution with a currentof high density.

4. A continuous electrolytic process for the extraction of zinc from azinc-bearing material which consists in forming there from aconcentrated solution of a zinc salt free from any colloid agent andcontaining an excess of acid, electrolyzing'the solution with a currentof high density, and then using theelcctrolyzed solution todissolvecharge of zinc-bearing material in such a maner as to retainthe.

the zinc in a fresh acid content of the solution at its originalconcentratlon. I

5. A continuous electrolytic process for material which consists informing therefrom a concentrated solution of a zinc. salt free from-anycolloid agent and. containing an excess of acid, electrolyzing the,solution with a current of high density, regenerating the said solutionby dividing it into two portions in such proportions that, when the acidin one portion is neutralized by the addition to it of a charge ofzinc-bearing material and the resulting solution sepa-' rated from theresidue and mixed with the other, portion of the electrolyzed solutionwhich has been retained, the acid content of the -final solutlon shallbe approximately the lytic extraction of then electrolyzmg theregenerated so ution with a'current of highdensity.

{6; 'ruminants' prodess iofii thetelectro metallic zmc from azinc-bearing mate ial which consists in addingsuflicienfiof-"-thezinc-bearing material toan acid to make a neutral solution frfrom anycolloid ageii separating neut ialsse u from h=iofi$ a adding an excessof acid, electrolyzin g said solution by means rofs -,currentgofggllighdensity and il'llillS ,remotin parteo'f o hezizli then removing] ,thei;solut1ou- :,=n0W Strongly acid and; dividing it lnmxtWQ portions; neu:

of zinc-be'aringimaterial, separating theneutral solution from theresidue; ,jadding; the other portion of the remoyed so lution andelectrolyzingt the acid; solution 1 so forrned,

tralizing one, portion by a; further faddition a P and thereafter,repeating the 'regen ating at and electroly z lng process as: describedIn testimony. whereof wel have s gne 1 our names to thisspecificationin, the presence of two subscribing witnesses.

URLYN ;.CL FT N TAINTO JOHN NORM N r Witnesses; to signature; of Ur lynClifton Taintonz 5 L Bo om,

CnasiRocnns. Witnesses to signature of J.

a WM. W; BRQISSVWICK a consrnn'rf-Gunaann,

PRING-

